The invention relates to a high security lock, particularly for use with powder magazines or storing blasting explosives in remote wilderness areas, the explosives being used for mining, road construction, etc.
To reduce risk of unauthorized use or theft of explosives, the explosives are transported under relatively high security from a central explosive storage area to the remote magazine, which is typically a reinforced building with a door secured with a keyed lock. When unauthorized persons wish to break into such a building, the lock itself is often considered to be the weakest portion of the security system, and many locks commonly yield to forced entry by using relatively simple tools, e.g. a crowbar. Alternatively, often the door can be pulled open using a chain connected to the door and to a conventional pick-up truck. Because the building is located in a remote area, the unauthorized person usually has adequate time to effect the break in, and excessive noise is not a problem.
Government regulations require a lock of a certain standard to secure the door, but commonly such a lock can be easily forced and cost constraints prevent the use of more expensive and complicated locks. In addition, because the building is exposed to the elements, and often subjected to extreme temperatures, the lock itself cannot be excessively sophisticated or sensitive to excessive moisture or temperature fluctuations otherwise it would be prone to jam, and thus would be difficult for an authorized person to gain access to the explosives.
It is known to provide a locking apparatus in which a handle which activates a mechanism to move slideable door bolts to secure a door can be selectively disengaged from the mechanism to permit free rotation of the handle without actuating the door bolts. One such device is disclosed in German Patent Publication DE 94 13 552 U (Hoppe AG) which discloses a relatively complex structure in which an actuating handle can be disengaged from a mechanism to actuate door bolts when a key controlling the lock is rotated in one direction, and can be engaged when the key is rotated in an opposite direction. While such a structure might be appropriate in some relatively controlled environments, it would be inappropriate in the extreme temperatures to which powder magazines are exposed as it is relatively complex and vulnerable to forced entry.
U.S. Pat. No. 4,690,073 (Shoop) discloses a locking mechanism in which a pair of coupled locks are linked to a rotatable handle mechanism in such a way that the handle is free for rotation when the door is secured, and is engaged with door bolt actuating mechanism when the door is to be opened. The structure is relatively complex and occupies some considerable space on an inside surface of the secured door, and can be vulnerable to forced entry as the actuating handle for the door bolts is permanently secured to the door.
The present invention reduces the difficulties and disadvantages of the prior art by providing a high security lock apparatus in which the strength of the keyed lock has no bearing on the overall security of the locked door itself. The keyed lock can be a conventional Yale-type deadbolt lock which, when the lock apparatus according to the invention is secured, the deadbolt of the keyed lock is retracted, which contrasts with all locks known to the inventor in which, when the lock is secured, the deadbolt is always extended. When the deadbolt of the present invention is retracted, movement of external structure associated with the deadbolt does not open the door, and thus use of excessive force on the external structure associated with the deadbolt does not cause the door to be opened. In addition, the invention provides one or more doorbolts which can be suitably rugged and reinforced to secure the door within the door frame, the doorbolts being actuated by linkage structure which in turn is actuated by the keyed deadbolt in such a way that only when the deadbolt of the keyed lock is extended can the doorbolts be actuated.
A high security lock apparatus according to the invention is for controlling position of a moveable doorbolt with respect to a door, and comprises a deadbolt lock and a lock body support. The deadbolt lock has a lock body and a deadbolt extendible therefrom. The lock body support cooperates with the lock body to permit relative movement therebetween and has a deadbolt clearance opening therein to receive the deadbolt when extended and aligned therewith to prevent said relative movement. The lock body support is operatively connected to the doorbolt to selectively extend or retract the doorbolt when the deadbolt is extended and the lock body is moved.
The apparatus further comprises a tool receiver which can cooperate with the lock body support to receive an alignment tool for generating movement between the lock body and the lock body support to align the deadbolt with the deadbolt clearance opening. Preferably, the lock body is journalled for rotation relative to the lock body support, and also both the lock body and lock body support are rotatable about a main axis of the apparatus.
Preferably, the lock body support has an actuating arm extending therefrom and a doorbolt link extends from the actuating arm to the doorbolt to operatively connect them together to actuate the doorbolt. A secondary lock having a secondary lock body and a secondary bolt extendible therefrom can interfere with the lock body support to prevent movement thereof.
An alternative embodiment of the invention is a high security lock apparatus which comprises an engager, an engager body support, and a doorbolt. The engager has an engager body and is mounted for primary movement and has actuated and non-actuated conditions. The engager body support cooperates with the engager body to permit said primary movement between the engager and the engager body when the engager is non-actuated. The engager body is selectively positionable relative to the engager body support to prevent said movement when the engager is actuated. The doorbolt is operatively connected to the engager body support to be moved when the engager is actuated and moved.
An alternative lock apparatus according to the invention is for installation in a member and comprises a lock body having a body face with a key opening to receive a key. An access opening in the member extends from adjacent the key recess on the body face to an outside face of the member, the access opening being sufficiently large to receive the key for accessing the key hole, but being sufficiently small to prevent manipulation of lock picking tools.
A detailed disclosure following, related to drawings, describes embodiments of the invention which is capable of expression in structure other than that particularly described and illustrated.